Enantioselective Access to Decahydroquinolines Bearing a C or C Quaternary Stereocenter from a Common Intermediate Total Synthesis of (-)-Myrioxazine A.

()-Phenylglycinol-derived perhydrooxazoloquinoline provides stereoselective access to angularly substituted enantiopure decahydroquinolines (DHQs). Reaction of with appropriate Grignard reagents leads to -DHQs bearing a C aza-quaternary stereocenter, whereas reaction of with Michael acceptors followed by reductive removal of the 2-phenylethanol of the chiral inductor gives rise to - or -DHQs bearing a C4a all-carbon quaternary stereocenter depending on the hydride used for the cleavage of the oxazolidine C-O bond. Theoretical studies have clarified the mechanistic intricacies of the reaction of with Michael acceptors, providing arguments for a proper understanding of the observed stereoselectivity. Finally, the reaction of with formaldehyde is reversible, allowing the regioselective formation of either the angularly substituted hydroxymethyl derivative or the C-substituted derivative depending on the reaction temperature. An expeditious synthesis of the -type alkaloid (-)-myrioxazine A from is reported.